“Assist as needed” control algorithms promote activity of patients during robotic gait training. Implementing these requires a free walking mode of a device, as unassisted motions should not be hindered. The goal of this study was to assess the normality of walking in the free walking mode of the LOPES gait trainer, an 8 degrees-of-freedom lightweight impedance controlledexoskeleton. Kinematics, gait parameters and muscle activity of walking in a free walking mode in the device were compared with those of walking freely on a treadmill. Average values and variability of the spatio-temporal gait variables showed no or small (relative to cycle-to-cycle variability) changes and the kinematics showed a significant and relevant decrease in knee angle range only. Muscles involved in push off showed a small decrease, whereas muscles involved in acceleration and deceleration of the swing leg showed an increase of their activity. Timing of the activity was mainly unaffected. Most of the observed differences could be ascribed to the inertia of the exoskeleton. Overall, walking with the LOPES resembled free walking, although this required several adaptations in muscle activity. These adaptations are such that we expect that Assist as Needed training can be implemented in LOPES.

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This study presents a three control degrees of freedom myoelectric control scheme that employs an independent signal for thumb flexion intended to allow for multiple gripping patterns. This scheme is designed to work with an adaptive grasp prosthesis designed in a parallel study. The control scheme is designed and employed using LabVIEW 8.2®. Human subject testing is conducted to evaluate functionality, perceived ease of learning, and perceived ease of control for both genders. Testing indicated that independent control of thumb flexion and generating DC motor drive signals for multiple grips was possible (success rate ≥83%). A visual analog scale score of 9.28/10 indicated that the system and the program user interface were very easy to learn. A visual analog scale score of 6.3/10 indicated that the system was fairly easy to control. A marginally significant difference (p = 0.057) was observed between genders, where females perceived the system to be easier to control than males.

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This paper proposes a knee joint moment estimating algorithm which utilizes the surface EMGs of involved muscles and joint angle kinematic data. This algorithm will be essential part for the control system design of exoskeletal robotic devices. In order for this algorithm to accurately predict joint moments, it is necessary to know the one’s musculo-skeletal properties, which is virtually impossible. An optimization process is used to determine one’s musculo-tendon characteristics. The proposed method is evaluated through the comparison with the isokinetic experimental results. Based on the analysis on this comparison, it is claimed that the gravity compensation data of the dynamometer (CON-TREX MJ system) contains not only purely gravity compensated portion but also the knee joint moment contributed by the passive muscle fiber forces.

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Neurological injuries caused by stroke, spinal cord injury or other illnesses and accidents often lead to walking disabilities. If not properly treated, gait disorders can lead to impaired physical and mental health, reduced physical activity, falls, fear of falling, loss of independence and the need for continuous medical care. After an accident or the start of an illness it is important to start the patient’s gait rehabilitation process as soon as mental and physical conditions allow. Robotized rehabilitation systems have a number of potential benefits over traditional manual rehabilitation. These benefits include an increase in the effectiveness of the rehabilitation process, reduced costs of rehabilitation and reduced need for trained medical personnel. This paper presents details of the development of the concept of a mobile gait rehabilitation system consisting of a mobile base and powered exoskeleton. In particular, modeling and simulation of its mechanical system are considered. The presented simulation results demonstrate the need for including actuated translational degrees of freedom between the support platform and the exoskeleton to allow displacement of patient’s pelvis and practice of dynamically balanced walking.

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The following topics are dealt with: intelligent robots and systems; SLAM: features and bias issues; humanoid robots; human-robot interaction; sensor networks; sensors for robot localization; under-actuated manipulation; robot learning; mobile robot localization; robot audition; multi-robot systems; vision and applications; motion planning; unmanned aerial vehicles; SLAM: loop closing; bio-applications for microrobots; parallel manipulator analysis; incremental mapping; SLAM algorithms; haptic display; micro/nano manipulation; stereo vision; micro/nano sensing and manipulation; behavior learning; multi-modal sensing; vision calibration; task planning; planetary rovers; SLAM: data association; service robots; redundancy control; learning by interaction; contact dynamics; shape/profile measurement; visual servo; mobile robot control; underwater robots; range sensing based SLAM; demining robots; learning for robot control; tactile sensing; 3D SLAM; teleoperation; socially friendly robots; manipulator motion planning; neural controller for robots; actuators; range sensing; wheelchair robots; SLAM: map building; human-robot emotion; biomimetic robots and systems; compliant motion control; probabilistic methods in robotics; force/torque sensing; welfare robots; bearing only SLAM; biped robots; interaction and intelligence; telemanipulation; vision for reconstruction and monitoring; control of flexible robots; neural fuzzy computing; grasp planning and optimization; real-time vision; cooperative sensing; vision and environmental structure; snake robots; surgical robots; vision based SLAM; exoskeletons; time-delay in teleoperation; mobile robot scheduling and coverage; sliding mode control; robot software and programming; multi-fingered manipulation; vision sensors; multi-robot control; vision and planning; new concepts and techniques in teleoperation; unique robots and their control; grasp analysis; face/person recognition; pattern formation and control; vision architectur

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